fix_bug_on_finalizer_of_main_thread-1.9.3.patch

diff --git a/gc.c b/gc.c
index 01d908d..ba9726c 100644
--- a/gc.c
+++ b/gc.c
@@ -2042,12 +2042,14 @@ finalize_list(rb_objspace_t *objspace, RVALUE *p)
        RVALUE *tmp = p->as.free.next;
        run_final(objspace, (VALUE)p);
        if (!FL_TEST(p, FL_SINGLETON)) { /* not freeing page */
-            if (objspace->heap.sweep_slots) {
-                p->as.free.flags = 0;
-            }
-            else {
-                GC_PROF_DEC_LIVE_NUM;
-                add_freelist(objspace, p);
+            if ((VALUE)p != rb_thread_main()) {
+                if (objspace->heap.sweep_slots) {
+                    p->as.free.flags = 0;
+                }
+                else {
+                    GC_PROF_DEC_LIVE_NUM;
+                    add_freelist(objspace, p);
+                }
             }
        }
        else {
@@ -3048,7 +3050,8 @@ static int
 chain_finalized_object(st_data_t key, st_data_t val, st_data_t arg)
 {
     RVALUE *p = (RVALUE *)key, **final_list = (RVALUE **)arg;
-    if ((p->as.basic.flags & (FL_FINALIZE|FL_MARK)) == FL_FINALIZE) {
+    if ((p->as.basic.flags & (FL_FINALIZE|FL_MARK)) == FL_FINALIZE &&
+        (VALUE)p != rb_thread_main()) {
        if (BUILTIN_TYPE(p) != T_ZOMBIE) {
            p->as.free.flags = FL_MARK | T_ZOMBIE; /* remain marked */
            RDATA(p)->dfree = 0;